F. Biancaniello, S. D. Ridder, National Institute of Standards and Technology, Gaithersburg, MD
Fully austenitic high nitrogen stainless steels (HNSS) are a class of materials that demonstrate an attractive combination of strength, ductility and corrosion resistance properties. Increased solubility of constituents, enhanced microstructural refinement and chemical homogeneity are the results of the rapid solidification occurring during the atomization of the powder. A predictive model was utilized to develop a series of HNSS alloys that do not exhibit the detrimental brittle intermetallics prevalent in these types of materials. The resulting reduction in quench rate sensitivity promotes the production of thicker component sections. An additional important property of these alloys is that the hardness and strength can be greatly improved through cold work without the threat of stress induced martensitic forming as is common in most other austenitic stainless steels.
Summary: Fully austenitic high nitrogen stainless steels (HNSS) are a class of materials that demonstrate an attractive combination of strength, ductility and corrosion resistance properties. Increased solubility of constituents, enhanced microstructural refinement and chemical homogeneity are the results of the rapid solidification occurring during the atomization of the powder. A predictive model was utilized to develop a series of HNSS alloys that do not exhibit the detrimental brittle intermetallics prevalent in these types of materials. The resulting reduction in quench rate sensitivity promotes the production of thicker component sections. An additional important property of these alloys is that the hardness and strength can be greatly improved through cold work without the threat of stress induced martensitic forming as is common in most other austenitic stainless steels.
